1. Field of the Invention
The present invention relates to an indicator in which a transmittable indicator panel is attached to a housing, indicates a character or a graphic form and the character or the graphic form is lighted by a light source provided in the housing.
2. Description of Background Art
FIGS. 9(a) and 9(b) are explanatory drawings for explaining a conventional type indicator, FIG. 9(a) being a front view and FIG. 9(b) being a side sectional view.
As shown in FIG. 9(a), the conventional type indicator 210 is an indicator in which a translucent indication area 212 is formed in an indicator panel 211. An indicated character 213 that does not transmit light is printed on the indication area 212. As shown in FIG. 9(b), the indicator panel 211 is lighted from the back by a light emitting diode 214, and the indicated character 213 can be also read at night by transmitting light from the light emitting diode 214.
Examples of attempted improvements to make indicator 210 clearer are shown in 1) “Light emitting diode bulb-type indicator” disclosed in Japanese published unexamined patent application No. Hei10-240142, and 2) “Indicator” disclosed in Japanese published unexamined patent application No. Hei11-51709.
In above 1), as shown in FIGS. 3 and 4 in the patent application, a board 37 is attached to a cup-shaped base 36 (a reference number used in the patent application is used as it is). A light emitting diode bulb 38 is attached to the board 37, an inner lens 21 collectively covers the board 37 and the light emitting diode bulb 38, and a concave portion 41 for widening the optical axis of the light emitting diode bulb 38 is formed in the inner lens 21. The indicator is prevented from being highlighted more than required at night by diffusing the quantity of light emitted from the light emitting diode bulb 38.
In above 2), as shown in FIG. 1 in the patent application, the improvement of the visibility of the following indication area S is attempted by attaching a light emitting diode (LED) 13 to a printed wiring board 4, covering the circumference of LED 13 with a case 1, and putting an indicator panel 6 on the case 1. An indication area S including a translucent layer 14 and a colored layer 15 is provided to the indicator panel 6, and the remaining area except the indication area S is masked with an opaque ground-color layer 9.
However, in the light emitting diode bulb-type indicator in the above 1), even though the indicator can be prevented from being highlighted more than required at night by diffusing the quantity of light emitted from the light emitting diode bulb 38, an indicated character cannot be always made clear.
In addition, in the indicator in the above 2), even though the visibility of the indication area S can be improved by masking the area except for the indication area S with the opaque ground-color layer 9, the colored layer 15 (the indicated character) is not always clear.
That is, an indicator that can indicate a character or a graphic form clearly both in the daytime and at night is desired.